A traditional Chinese medicine transportation packaging composite material with moisture absorption and slow-release antibacterial functions and a preparation method thereof

Abstract

This invention belongs to the field of packaging materials technology, specifically a composite material for transporting traditional Chinese medicine materials with both moisture absorption and slow-release antibacterial functions, and its preparation method. The composite material includes a substrate support layer, a moisture-absorbing layer, a slow-release antibacterial layer, and an inner protective layer. This application uses a dedicated slow-release antibacterial layer preparation step to load a natural essential oil compound encapsulated with β-cyclodextrin into a porous starch-chitosan matrix. The encapsulation structure of β-cyclodextrin can delay the volatilization of essential oils, achieving long-lasting slow-release antibacterial effects and greatly improving the inhibition rate against common molds in traditional Chinese medicine materials such as Penicillium and Aspergillus. At the same time, the moisture-absorbing layer quickly absorbs moisture inside the packaging, controlling the humidity within a suitable range, destroying the conditions for microbial growth from the source, forming a synergistic protection of moisture absorption and control and slow-release antibacterial effects, making up for the shortcomings of traditional packaging's single moisture protection.

Description

Technical Field

[0001] This invention relates to the field of packaging materials technology, specifically to a composite material for transporting traditional Chinese medicine with both moisture absorption and slow-release antibacterial functions, and its preparation method. Background Technology

[0002] As the core carrier of my country's traditional medicine industry, the quality and stability of Chinese medicinal herbs directly determine their efficacy. These herbs are rich in active ingredients such as polysaccharides, proteins, and volatile oils. During long-distance transportation and storage, they are highly susceptible to environmental factors such as temperature and humidity, and microbial contamination, leading to problems like moisture absorption, mold growth, rot, insect infestation, and deterioration. This results in the loss of active ingredients, reduced efficacy, or even complete ineffectiveness, causing serious economic losses and resource waste. Statistics show that 8%-15% of Chinese medicinal herbs in my country deteriorate annually due to improper transportation and packaging, with moisture absorption and mold growth being the two core causes of quality deterioration. Therefore, developing specialized transport packaging materials with highly efficient moisture absorption, moisture-proofing, and continuous antibacterial functions is of great significance for ensuring the quality of Chinese medicinal herbs and promoting the standardized development of the Chinese medicine industry.

[0003] The following technical problems still exist in the use of composite materials for transporting and packaging Chinese medicinal materials:

[0004] Currently, the packaging materials for Chinese medicinal herbs on the market are traditional moisture-proof packaging, using polyethylene or polypropylene film composite paper materials, or placing independent desiccants such as silica gel or montmorillonite inside the packaging. These solutions only achieve basic moisture protection and lack antibacterial functions, failing to inhibit the growth and reproduction of mold and bacteria in humid environments. Furthermore, independent desiccants are prone to falling off and releasing moisture after absorbing it, exhibiting poor moisture absorption stability. Simultaneously, some desiccants may physically adsorb onto the medicinal herbs, affecting the retention rate of volatile oils and other active ingredients.

[0005] To address these issues, a composite material for transporting and packaging Chinese medicinal materials with both moisture absorption and slow-release antibacterial functions, along with its preparation method, is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a composite material for transporting Chinese medicinal materials that combines moisture absorption and slow-release antibacterial functions, as well as its preparation method, in order to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a composite material for transporting Chinese medicinal materials that combines moisture absorption and slow-release antibacterial functions, the composite material comprising a substrate support layer, a moisture-absorbing layer, a slow-release antibacterial layer, and an inner protective layer; The substrate support layer is the outermost layer, specifically a modified plant fiber composite paper material; The moisture-absorbing layer is bonded and fixed to the inner wall of the substrate support layer. The moisture-absorbing layer is prepared by using modified inorganic moisture-absorbing powder and environmentally friendly binder. The slow-release antibacterial layer is bonded and fixed to the inner wall of the moisture-absorbing layer. The slow-release antibacterial layer is prepared by combining natural antibacterial components and a slow-release carrier. The inner protective layer is bonded and fixed to the inner wall of the slow-release antibacterial layer, and the inner protective layer is made of food-grade breathable cotton paper.

[0008] Preferably, the modified plant fiber composite paper is prepared by mixing and modifying bamboo fiber with softwood pulp and then combining it with a low basis weight polypropylene nonwoven fabric reinforcement layer.

[0009] Preferably, the environmentally friendly binder in the moisture-absorbing layer is sodium carboxymethyl cellulose, and the moisture-absorbing powder is prepared by mixing surface-inert silica-montmorillonite composite powder with a small amount of sodium polyacrylate water-absorbing resin.

[0010] Preferably, the antibacterial component in the sustained-release antibacterial layer is a thymol-citronellol essential oil complex encapsulated by β-cyclodextrin, and the sustained-release carrier is a porous starch and chitosan composite matrix.

[0011] Preferably, the food-grade breathable cotton paper in the inner protective layer needs to be sterilized at high temperature before use.

[0012] A method for preparing a composite material for transporting traditional Chinese medicine materials that combines moisture absorption and sustained-release antibacterial functions, the specific steps of which are as follows: S1. Raw material pretreatment: S1.1, Pretreatment of substrate support layer raw materials: Take bamboo fiber and softwood pulp at a mass ratio of 7:3, add deionized water to make a slurry, add 0.4-0.5% cationic starch modifier of the total slurry mass, and stir at 40-50℃ for 20-30 minutes for modification treatment; at the same time, prepare a quantitative amount of 30-40 Low-weight polypropylene nonwoven fabric is sterilized by ultraviolet light for 10-15 minutes before use. S1.2 Pretreatment of moisture-absorbing layer raw materials: Mix silica gel and montmorillonite powder at a mass ratio of 3:1, add 1.5-2% of silane coupling agent (KH-550) of the total powder mass, and stir at high speed at 60-80℃ for 20 minutes to complete the surface inert treatment; then mix with sodium polyacrylate water-absorbing resin at a mass ratio of 9:1 to obtain modified moisture-absorbing powder; prepare an environmentally friendly binder by mixing sodium carboxymethyl cellulose and deionized water at a mass ratio of 1:10, and stir until completely dissolved; S1.3 Pretreatment of raw materials for slow-release antibacterial layer: Take thymol and lemongrass essential oil at a mass ratio of 1:1, add 2-2.5 times the mass of β-cyclodextrin, stir at 50-60℃ and 300r / min for 50-60min, cool to room temperature, centrifuge, and dry to obtain an essential oil compound with an inclusion rate ≥85%; Take porous starch and chitosan at a mass ratio of 4:1, add deionized water to prepare a carrier matrix with a mass fraction of 10%, and set aside. S1.4 Inner protective layer raw material pretreatment: Take food-grade breathable cotton paper, put it into a high-pressure steam sterilizer at 100-120℃ for 15-20 minutes, take it out and let it air dry naturally in a clean environment to avoid secondary contamination and ensure safety in contact with Chinese medicinal materials. S2, Functional layer preparation: S2.1 Preparation of substrate support layer: Modified bamboo fiber-coniferous wood pulp is formed using a long-wire paper machine and dried to a moisture content of ≤8% to obtain the base paper layer; Polypropylene nonwoven fabric is laminated to one side of the base paper layer with a starch-based adhesive and hot-pressed at 60-70℃. S2.2 Preparation of the moisture-absorbing layer: Modified moisture-absorbing powder is added to sodium carboxymethyl cellulose binder and stirred to prepare a moisture-absorbing slurry with a solid content of 25-30%. This slurry is then uniformly coated onto the inner wall of the substrate support layer using a doctor blade coating process, with a coating amount of 20-25g. Then, it is dried with hot air at 50-60℃ for 30-40 minutes to form a continuous and dense moisture-absorbing film. S2.3 Preparation of sustained-release antibacterial layer: Add the β-cyclodextrin-encapsulated essential oil compound to the porous starch-chitosan carrier matrix and ultrasonically disperse for 15-20 min to ensure that the essential oil compound is uniformly loaded in the carrier; use an impregnation process to immerse the inner wall of the moisture-absorbing layer into the mixed system for 15 min, and then remove it and vacuum dry at 40-50℃ for 25-30 min; S2.4 Inner protective layer preparation: Sterilized food-grade breathable cotton paper is laminated to the inner wall of the slow-release antibacterial layer using a water-based adhesive and then hot-pressed at a low temperature of 50-65℃. S3. Composite molding and post-processing: The prepared composite material consisting of a substrate support layer, a moisture-absorbing layer, a slow-release antibacterial layer, and an inner protective layer is placed in a constant temperature and humidity chamber for equilibration for 22-24 hours. According to the actual transportation and packaging requirements, the composite material is cut and the edges are sealed using a heat-sealing process to avoid interlayer peeling. Finally, after testing for appearance, moisture absorption, and antibacterial activity, qualified products are considered to be composite materials for transporting Chinese medicinal materials that combine moisture absorption and slow-release antibacterial functions.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1) This application uses a proprietary slow-release antibacterial layer preparation step to load a natural essential oil compound encapsulated with β-cyclodextrin into a porous starch-chitosan matrix. The encapsulation structure of β-cyclodextrin can delay the volatilization of essential oils, achieving long-lasting slow-release antibacterial effect and greatly improving the inhibition rate against common molds in Chinese medicinal materials such as Penicillium and Aspergillus. At the same time, the moisture-absorbing layer quickly absorbs moisture inside the packaging, controlling the humidity within a suitable range and destroying the conditions for microbial growth from the source, forming a synergistic protection of moisture absorption and control and slow-release antibacterial effect, making up for the shortcomings of traditional packaging that only provides moisture protection. 2) In this application, the moisture-absorbing layer is integrally formed with the substrate support layer by a scraper coating process, eliminating the risk of independent desiccant falling off. In the raw material pretreatment, the silica-montmorillonite powder is surface inertized and sodium polyacrylate water-absorbing resin is added to adjust the moisture absorption performance, so that the moisture-absorbing layer forms a stable gel state after absorbing moisture, avoiding the reverse release of water after the traditional desiccant is saturated, and adapting to the needs of long-distance transportation. 3) In this application, the hygroscopic layer powder is surface inertly treated with silane coupling agent, which greatly reduces its adsorption activity on the volatile oil of Chinese medicinal materials. The inner protective layer is made of sterile and breathable cotton paper to form a physical isolation, avoiding direct contact between the hygroscopic powder, antibacterial components and Chinese medicinal materials. At the same time, the substrate support layer is made of low-adsorption modified plant fiber, which can improve the retention rate of volatile oil of Chinese medicinal materials and ensure the stability of efficacy. Attached Figure Description

[0014] Figure 1 This is a composition diagram of the composite material in this invention; Figure 2 This is a flowchart illustrating the preparation steps of the composite material of the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Example: Please see Figure 1-2 The present invention provides a technical solution: A composite material for transporting Chinese medicinal materials that combines moisture absorption and slow-release antibacterial functions includes a substrate support layer, a moisture-absorbing layer, a slow-release antibacterial layer, and an inner protective layer. The substrate support layer is the outermost layer, specifically a modified plant fiber composite paper material; The moisture-absorbing layer is bonded and fixed to the inner wall of the substrate support layer. The moisture-absorbing layer is prepared by using modified inorganic moisture-absorbing powder and environmentally friendly binder. The slow-release antibacterial layer is bonded and fixed to the inner wall of the moisture-absorbing layer. The slow-release antibacterial layer is prepared by combining natural antibacterial components and a slow-release carrier. The inner protective layer is bonded and fixed to the inner wall of the slow-release antibacterial layer, and the inner protective layer is made of food-grade breathable cotton paper.

[0017] The modified plant fiber composite paper is prepared by mixing and modifying bamboo fiber with softwood pulp and then adding a low-basis-weight polypropylene nonwoven fabric reinforcement layer.

[0018] The environmentally friendly binder in the moisture-absorbing layer is sodium carboxymethyl cellulose, and the moisture-absorbing powder is prepared by mixing surface-inert silica-montmorillonite composite powder with a small amount of sodium polyacrylate water-absorbing resin.

[0019] The antibacterial component in the sustained-release antibacterial layer is a thymol-citronella oil complex encapsulated by β-cyclodextrin (encapsulation rate ≥85%), and the sustained-release carrier is a porous starch and chitosan composite matrix.

[0020] The food-grade breathable cotton paper in the inner protective layer needs to be sterilized at high temperature before use.

[0021] A method for preparing a composite material for transporting traditional Chinese medicine materials that combines moisture absorption and sustained-release antibacterial functions, the specific steps of which are as follows: S1. Raw material pretreatment: S1.1, Pretreatment of substrate support layer raw materials: Take bamboo fiber and softwood pulp at a mass ratio of 7:3, add deionized water to make a slurry, add 0.4-0.5% cationic starch modifier of the total slurry mass, stir at 40-50℃ for 20-30 minutes for modification treatment to improve fiber bonding strength; at the same time, prepare a quantitative amount of 30-40 Low-weight polypropylene nonwoven fabric is sterilized by ultraviolet light for 10-15 minutes before use. Bamboo fiber and softwood pulp are mixed in a 7:3 ratio and modified with cationic starch to improve the fiber bonding strength of the pulp and the physical strength of the paper. This solves the problems of insufficient support and easy damage during transportation of pure plant fiber paper, and meets the requirements of packaging for load-bearing and impact resistance. The low basis weight polypropylene nonwoven fabric is sterilized by ultraviolet light to ensure the sterility of the reinforcing layer raw materials and avoid the nonwoven fabric from carrying microorganisms that could contaminate the Chinese medicinal materials. At the same time, the low basis weight design does not increase the overall weight and thickness of the packaging while enhancing the support of the base material, making it suitable for the portability of transport packaging. The 40-50℃ constant temperature stirring modification ensures that the cationic starch and pulp are fully mixed, the modification effect is uniform, and the local paper strength difference is avoided.

[0022] S1.2 Pretreatment of moisture-absorbing layer raw materials: Mix silica gel and montmorillonite powder at a mass ratio of 3:1, add 1.5-2% of silane coupling agent (KH-550) of the total powder mass, and stir at high speed at 60-80℃ for 20 minutes to complete the surface inert treatment and reduce the adsorption activity on the volatile oil of Chinese medicinal materials; then mix with sodium polyacrylate water-absorbing resin at a mass ratio of 9:1 to obtain modified moisture-absorbing powder; prepare an environmentally friendly binder by mixing sodium carboxymethyl cellulose and deionized water at a mass ratio of 1:10 and stir until completely dissolved; Silica gel and montmorillonite powders are blended in a 3:1 ratio, combining the advantages of two inorganic moisture-absorbing materials (silica gel has a large moisture absorption capacity, and montmorillonite has strong adsorption properties due to its interlayer structure), thus improving the overall moisture absorption capacity of the powder. A silane coupling agent is added for surface inert treatment to prevent powder agglomeration and improve its dispersibility in the binder, ensuring uniform coating of the subsequent moisture-absorbing layer. The moisture-absorbing powder is blended with sodium polyacrylate water-absorbing resin in a 9:1 ratio, with the inorganic powder and organic water-absorbing resin working synergistically to balance moisture absorption speed and water retention, solving the problems of easy saturation and desorption of single moisture-absorbing materials, and meeting the continuous moisture absorption requirements of long-distance transportation of Chinese medicinal materials. Sodium carboxymethyl cellulose is prepared as a binder at a 1:10 ratio and stirred until completely dissolved, ensuring the film-forming properties and adhesion of the binder, providing a foundation for the subsequent coating and molding of the moisture-absorbing powder. Furthermore, sodium carboxymethyl cellulose is an environmentally friendly water-soluble binder, meeting the environmental protection requirements for packaging Chinese medicinal materials.

[0023] S1.3 Pretreatment of raw materials for slow-release antibacterial layer: Take thymol and lemongrass essential oil at a mass ratio of 1:1, add 2-2.5 times the mass of β-cyclodextrin, stir at 50-60℃ and 300r / min for 50-60min, cool to room temperature, centrifuge, and dry to obtain an essential oil compound with an inclusion rate ≥85%; Take porous starch and chitosan at a mass ratio of 4:1, add deionized water to prepare a carrier matrix with a mass fraction of 10%, and set aside. A 1:1 blend of thymol and lemongrass essential oils provides synergy between the two natural antibacterial components, broadening the antibacterial spectrum. It inhibits common molds and bacteria found in traditional Chinese medicine, such as Aspergillus and Escherichia coli, with no natural residues, meeting the safety requirements for packaging traditional Chinese medicine. The essential oil blend is encapsulated with β-cyclodextrin, achieving a sustained-release basis for the antibacterial components and addressing the issues of volatility and short-term antibacterial effect of essential oils. This allows the antibacterial components to be released slowly during transportation, ensuring long-lasting antibacterial effects. A process involving stirring at 50-60℃ and centrifugal drying ensures a thorough encapsulation reaction and improves the encapsulation rate. A 10% carrier matrix is ​​prepared using a 4:1 ratio of porous starch and chitosan. The porous structure of the starch provides ample loading sites for the encapsulated essential oils, ensuring uniform dispersion of the antibacterial components. Chitosan itself possesses weak antibacterial properties, synergistically enhancing the antibacterial effect with the essential oils. Simultaneously, the film-forming properties of chitosan support the subsequent formation of the sustained-release antibacterial layer.

[0024] S1.4 Inner protective layer raw material pretreatment: Take food-grade breathable cotton paper, put it into a high-pressure steam sterilizer at 100-120℃ for 15-20 minutes, take it out and let it air dry naturally in a clean environment to avoid secondary contamination and ensure safety in contact with Chinese medicinal materials. S2, Functional layer preparation: S2.1 Preparation of substrate support layer: Modified bamboo fiber-coniferous wood pulp is formed using a long-wire paper machine and dried to a moisture content of ≤8% to obtain the base paper layer; Polypropylene nonwoven fabric is laminated to one side of the base paper layer with a starch-based adhesive and hot-pressed at 60-70℃ (pressure 0.3MPa, time 20s) to form a substrate support layer that has both mechanical strength and breathability. The modified pulp is formed and dried to a moisture content of ≤8% using a long-wire paper machine, ensuring the formability and dryness of the base paper layer and preventing the medicinal materials from absorbing moisture and becoming damp. At the same time, the long-wire forming process ensures uniform fiber distribution in the paper layer, improving overall strength. The polypropylene nonwoven fabric is bonded to the paper layer through a starch-based binder and hot-pressed at 60-70℃, achieving a strong bond between the paper layer and the nonwoven fabric. This improves the overall support, folding resistance, and tear resistance of the base material, making it suitable for collisions and stacking during transportation. The starch-based binder is environmentally friendly and biodegradable, matching the safety and environmental protection requirements for medicinal material packaging. Low-temperature hot pressing prevents the nonwoven fabric from aging.

[0025] S2.2 Preparation of the moisture-absorbing layer: Modified moisture-absorbing powder is added to sodium carboxymethyl cellulose binder and stirred to prepare a moisture-absorbing slurry with a solid content of 25-30%. This slurry is then uniformly coated onto the inner wall of the substrate support layer using a doctor blade coating process, with a coating amount of 20-25g. Then, it is dried with hot air at 50-60℃ for 30-40 minutes to form a continuous and dense moisture-absorbing film. Modified hygroscopic powder is mixed with a binder to form a hygroscopic slurry with a solid content of 25-30%. This ensures the slurry's fluidity and coatability, avoiding both excessively low solid content (leading to a thin hygroscopic layer and insufficient hygroscopic capacity) and excessively high solid content (leading to uneven coating). A doctor blade coating process is used to evenly coat the inner wall of the substrate, with the coating amount controlled at 20-25%. This process ensures the uniformity and continuity of the moisture-absorbing layer, allowing it to absorb moisture from the packaging during transportation. The coating on the inner wall of the substrate does not affect its external support performance. Hot air drying at 50-60℃ for 30-40 minutes allows the moisture-absorbing layer to quickly form and remain dry, creating a continuous and dense moisture-absorbing film. This enhances the adhesion between the moisture-absorbing layer and the substrate, preventing interlayer peeling. Low-temperature drying prevents the adhesive from aging and failing.

[0026] S2.3 Preparation of the sustained-release antibacterial layer: The β-cyclodextrin-encapsulated essential oil compound is added to a porous starch-chitosan carrier matrix and ultrasonically dispersed for 15-20 minutes (300W) to ensure that the essential oil compound is uniformly loaded in the carrier; the inner wall of the hygroscopic layer is immersed in the mixture for 15 minutes using an impregnation process, and then vacuum dried at 40-50℃ for 25-30 minutes to form a sustained-release antibacterial layer, achieving long-term slow release of natural essential oils and avoiding secondary contamination by chemical antibacterial agents; S2.4 Preparation of inner protective layer: Sterilized food-grade breathable cotton paper is laminated to the inner wall of the slow-release antibacterial layer with water-based adhesive and then hot-pressed at a low temperature of 50-65℃ (pressure 0.2MPa, time 15s) to ensure strong adhesion without damaging the structure of each functional layer, while forming a physical barrier to prevent moisture-absorbing powder, antibacterial ingredients and Chinese medicinal materials from direct contact. S3. Composite molding and post-processing: The prepared composite material consisting of a substrate support layer, a moisture-absorbing layer, a slow-release antibacterial layer, and an inner protective layer is placed in a constant temperature and humidity chamber (temperature 25℃, humidity 50%) for 22-24 hours to eliminate interlayer stress and improve structural stability. According to actual transportation and packaging requirements, the composite material is cut and edge-sealed using a heat-sealing process (temperature 100-120℃, time 3-5s) to prevent interlayer delamination. Finally, after testing for appearance, moisture absorption, and antibacterial activity, qualified products are considered to be composite materials for transporting Chinese medicinal materials that combine moisture absorption and slow-release antibacterial functions.

[0027] The composite material is placed in a constant temperature and humidity chamber for 22-24 hours to equilibrate, allowing the moisture content of each layer to reach equilibrium with the environment. This prevents warping, deformation, or delamination of the composite material due to temperature and humidity changes during subsequent transportation, ensuring the structural stability of the product. The equilibration process also verifies the strength of interlayer adhesion, proactively identifying potential delamination issues. The composite material is then cut and heat-sealed according to transportation packaging requirements, adapting it to different specifications of Chinese medicinal herb transport packaging. The heat-sealing process ensures a tight bond at the edges, preventing delamination during transport. Simultaneously, the sealed edges prevent external moisture and bacteria from entering the packaging, enhancing its airtight protection. After testing for appearance, moisture absorption, and antibacterial activity, the product is deemed qualified, achieving quality control: appearance inspection identifies process defects such as delamination, uneven coating, and inadequate sealing; moisture absorption testing ensures the composite material's moisture absorption capacity meets standards for long-distance transportation of Chinese medicinal herbs; and antibacterial activity testing ensures the potency and sustained-release effect of antibacterial components, effectively inhibiting mold growth in the Chinese medicinal herbs. Defective products are rejected to ensure the functional effectiveness and reliability of the final product.

[0028] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or basic characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of the invention is defined by the appended claims rather than the foregoing description. Therefore, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0029] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A composite material for transporting traditional Chinese medicine materials, possessing both moisture-absorbing and slow-release antibacterial functions, characterized in that... The composite material includes a substrate support layer, a moisture-absorbing layer, a slow-release antibacterial layer, and an inner protective layer; The substrate support layer is the outermost layer, specifically a modified plant fiber composite paper material; The moisture-absorbing layer is bonded and fixed to the inner wall of the substrate support layer. The moisture-absorbing layer is prepared by using modified inorganic moisture-absorbing powder and environmentally friendly binder. The slow-release antibacterial layer is bonded and fixed to the inner wall of the moisture-absorbing layer. The slow-release antibacterial layer is prepared by combining natural antibacterial components and a slow-release carrier. The inner protective layer is bonded and fixed to the inner wall of the slow-release antibacterial layer, and the inner protective layer is made of food-grade breathable cotton paper.

2. The composite material for transporting traditional Chinese medicine materials with both moisture absorption and slow-release antibacterial functions as described in claim 1, characterized in that: The modified plant fiber composite paper is prepared by mixing and modifying bamboo fiber with softwood pulp and then adding a low-basis-weight polypropylene nonwoven fabric reinforcement layer.

3. The composite material for transporting traditional Chinese medicine materials with both moisture absorption and slow-release antibacterial functions as described in claim 1, characterized in that: The environmentally friendly binder in the moisture-absorbing layer is sodium carboxymethyl cellulose, and the moisture-absorbing powder is prepared by mixing surface-inert silica-montmorillonite composite powder with a small amount of sodium polyacrylate water-absorbing resin.

4. The composite material for transporting traditional Chinese medicine materials with both moisture absorption and slow-release antibacterial functions as described in claim 1, characterized in that: The antibacterial component in the sustained-release antibacterial layer is a thymol-citronellol essential oil complex encapsulated by β-cyclodextrin, and the sustained-release carrier is a porous starch and chitosan composite matrix.

5. The composite material for transporting traditional Chinese medicine materials with both moisture absorption and slow-release antibacterial functions as described in claim 1, characterized in that: The food-grade breathable cotton paper in the inner protective layer needs to be sterilized at high temperature before use.

6. A method for preparing a composite material for transporting traditional Chinese medicine materials that combines moisture absorption and slow-release antibacterial functions according to any one of claims 1-5, characterized in that: The specific steps of this preparation method are as follows: S1. Raw material pretreatment: S1.1, Pretreatment of substrate support layer raw materials: Take bamboo fiber and softwood pulp at a mass ratio of 7:3, add deionized water to make a slurry, add 0.4-0.5% cationic starch modifier of the total slurry mass, and stir at 40-50℃ for 20-30 minutes for modification treatment; at the same time, prepare a quantitative amount of 30-40 Low-weight polypropylene nonwoven fabric is sterilized by ultraviolet light for 10-15 minutes before use. S1.2 Pretreatment of moisture-absorbing layer raw materials: Mix silica gel and montmorillonite powder at a mass ratio of 3:1, add 1.5-2% of silane coupling agent (KH-550) of the total powder mass, and stir at high speed at 60-80℃ for 20 minutes to complete the surface inert treatment; then mix with sodium polyacrylate water-absorbing resin at a mass ratio of 9:1 to obtain modified moisture-absorbing powder; prepare an environmentally friendly binder by mixing sodium carboxymethyl cellulose and deionized water at a mass ratio of 1:10, and stir until completely dissolved; S1.3 Pretreatment of raw materials for slow-release antibacterial layer: Take thymol and lemongrass essential oil at a mass ratio of 1:1, add 2-2.5 times the mass of β-cyclodextrin, stir at 50-60℃ and 300r / min for 50-60min, cool to room temperature, centrifuge, and dry to obtain an essential oil compound with an inclusion rate ≥85%; Take porous starch and chitosan at a mass ratio of 4:1, add deionized water to prepare a carrier matrix with a mass fraction of 10%, and set aside. S1.4 Inner protective layer raw material pretreatment: Take food-grade breathable cotton paper, put it into a high-pressure steam sterilizer at 100-120℃ for 15-20 minutes, take it out and let it air dry naturally in a clean environment to avoid secondary contamination and ensure safety in contact with Chinese medicinal materials. S2, Functional layer preparation: S2.1 Preparation of substrate support layer: Modified bamboo fiber-coniferous wood pulp is formed using a long-wire paper machine and dried to a moisture content of ≤8% to obtain the base paper layer; Polypropylene nonwoven fabric is laminated to one side of the base paper layer with a starch-based adhesive and hot-pressed at 60-70℃. S2.2 Preparation of the moisture-absorbing layer: Modified moisture-absorbing powder is added to sodium carboxymethyl cellulose binder and stirred to prepare a moisture-absorbing slurry with a solid content of 25-30%. This slurry is then uniformly coated onto the inner wall of the substrate support layer using a doctor blade coating process, with a coating amount of 20-25g. Then, it is dried with hot air at 50-60℃ for 30-40 minutes to form a continuous and dense moisture-absorbing film. S2.3 Preparation of sustained-release antibacterial layer: Add the β-cyclodextrin-encapsulated essential oil compound to the porous starch-chitosan carrier matrix and ultrasonically disperse for 15-20 min to ensure that the essential oil compound is uniformly loaded in the carrier; use an impregnation process to immerse the inner wall of the moisture-absorbing layer into the mixed system for 15 min, and then remove it and vacuum dry at 40-50℃ for 25-30 min; S2.4 Inner protective layer preparation: Sterilized food-grade breathable cotton paper is laminated to the inner wall of the slow-release antibacterial layer using a water-based adhesive and then hot-pressed at a low temperature of 50-65℃. S3. Composite molding and post-processing: The prepared composite material consisting of a substrate support layer, a moisture-absorbing layer, a slow-release antibacterial layer, and an inner protective layer is placed in a constant temperature and humidity chamber for equilibration for 22-24 hours. According to the actual transportation and packaging requirements, the composite material is cut and the edges are sealed using a heat-sealing process to avoid interlayer peeling. Finally, after testing for appearance, moisture absorption, and antibacterial activity, qualified products are considered to be composite materials for transporting Chinese medicinal materials that combine moisture absorption and slow-release antibacterial functions.

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